1. Field
Provided is a quantum dot (“QD”) light-emitting device or an organic light-emitting device (“OLED”), and method of fabricating the same, and more particularly, to a QD light-emitting device or an OLED having enhanced luminescence by using surface plasmon resonance and method of fabricating the same.
2. Description of the Related Art
An organic light-emitting device (“OLED”) uses a thin film formed of an organic material as an emitting layer. The OLED may be formed of various types of materials, such as a high-purity thin film. However, a lifetime of an organic light-emitting material of the OLED is relatively short, and a complicated and expensive film forming process is necessary.
Recently, research into a light-emitting device using quantum dot (“QD”) luminescence has been actively conducted. A QD is a semiconductor material that has a several-nanometer crystalline structure, each QD being smaller than a diameter of Bohr excitons. Although a large quantity of electrons exist in the QD, the number of free electrons from among the electrons is limited to between about 1 and about 100. As a result thereof, energy levels of the electrons in the QD are discontinuous. Thus, the QD has electric and optical characteristics that are different from those of a semiconductor in a bulk state which form a continuous band.
For example, since an energy level of the QD varies according to a size of the QD, it is possible to adjust a bandgap by simply changing the size of the QD. That is, an emitting wavelength of the QD may be adjusted by simply changing the size of the QD. This means that emitting of colors may be easily adjusted by changing the size of the QD. The QD has self-luminescence, ease in adjusting colors, and high color purity, and also a solution forming process is possible with respect to the QD. Thus, a QD light-emitting device may be used in a large next generation display having high display quality. However, in spite of the aforementioned merits, efficiency and brightness of the QD light-emitting device are not sufficient to be applied to a display.